Fuel injection system



Filed Jan. 2, 1948 IN VEN TOR. /T. @risa/75 Patented Nov. 27, 1951UNIT-ED STATES `PATENT OFFICE FUEL INJECTION SYSTEM en-'Gr.iParsons,Grosse Pointe, Mich.

Application January 2, 1948, .Serial No. 335

7 Claims. 1

This invention relates to improvements in fuel injection systems andmore Aparticularly to "improvements in gasoline fuel'injection systemsfor multi-cylinder engines.

One of the primary objects of the present invention is to provideimprovements in systems of the type mentioned wherein gasoline may bedistributed to a multiplicity `of cylinders in a'system employing asingle pump and distributor. A further object of the invention is toprovide improvementsv in systems of the type mentioned wherein the pumpmay be mounted in any convenient location land does not need to bemounted closely adjacent the engine cylinders and the necessity ot atransfer pump is eliminated,

A further object of the invention is to provide improvements in systemsof the type mentioned wherein means is provided which is responsive tothe engine manifold pressure so as to vary'the output of theaforementioned fuel pump. .A still further object of the invention istoprovide improvements in systems of the type mentioned wherein there willbe high delivery at low manifold pressure and low delivery at highmanifold pressure.

A still further object of the invention'is to provide, in theaforementioned manifold pressure responsive means, a high engine speedadjustment, and idling speed adjustment.

Other objects of the invention will become-apparent from the followingspecication, the drawings relating thereto, and from the claimsherelnafter set forth.

In the drawing in'whichlike numerals are used to designate like parts inthe several view throughout:

Figure l is a diagrammatic view ofthe mclin- `jection system accordingto .the present invention and showing the pump, distributor, andpressure responsive means, and the relation of the same to each otherand to the fuel tank and injector nozzles; and

Fig. 2 is a vertical cross sectional view ofthe distributor employedinFig. 1.

Referring to the drawing, a fuel supply tank is indicated at 3 having apump generally indicated at^5 mounted thereon. The pump is con`v` nectedto a vdistributor generally indicatedA at I through a flexible conduit9, andthe, distributor is connected to a plurality of .injector nozzlesII through flexible conduits I3. Thenozzles Il may be ofthe typedisclosed in the copending application of Ben G. Parsons, Serial No.546,352,1iled July 24, 1944, now abandoned, or'may be an open end tube.

The pump 5 comprises a housing I5 formedwith a longitudinally extendinginlet passageway l1. An inlet port I9'is located intermediate the endsof the housing I5 and communicates with the inlet passageway If'I andalso communicates through an inlet tube 2-I with the interior-of thetank 3. The

ltube 2|, of course, extends to a position adjacent sageway I'I'and thebores 23 and 25 extend through the ends of the housing I5 withinrecessed portions 2'l and 29. An end plate 3l is fixed to one end Vofthe housing and forms, between the 4inner face thereof and the recessy21, an inlet chamber communicating the adjacent end of the passagewayIl with the adjacent ends of thebores 23 and 25. An end member 33 isremovably attached to the opposite end of the housing I5 and is spacedfrom the recess 29 to provide an inlet chamber between the inner facethereof and recess 29 which communicates with that end of the passagewayI'I and with the adjacent ends of bores r23 and 25.

A pair of intermeshing pump elements 35 and 31 are disposed within thebores 23 and 25 respectively. Each of the pump elements 35 and 3l isthreaded with a lead extending from the outer ends of the elementstoward the center thereof Where the threads open into reduced portions39 and 4I. 'The outer ends of the threads ofthe pump elementscommunicate with the inlet chambers opposite the ends of the housing I5.The reduced portions 39 and 4I form with the adjacent peripheries of thebores 23 and 25 an outlet chamber vv-hich communicates through an outletport43 with conduit 9 which is attached to the housing l'adjacent theoutlet '43 by means of a fitting'44'.

One of the pump elements, for example, .element 35, is driven by anelectric motor 45 which is connected to the end member 33. The motor haslits drive rshaft received within a suitable bear ing mounted in themember A33 in axialalign', ment` with the element 35. The motor shaft iscoupled to an inwardly projecting end 49 of the eiement35 by means of acoupling indicated at 5 I'.

A manifold. pressure responsive unit, generally indicated at 53, isprovided for controlling the speed of the motory d5'. The unit 53consists of a hollow housing '55 having an enlarged recess -5-1 formedin one end thereof. The Wall of the hous ing 55', at the. enlarged end`thereof, isiformedfw'ith an outturned annular lflange 59. An end cap`Iii is secured to the enlarged end of the housing 55 by means of areversely bent annular flange 63, which embraces the housing flange 55T-The end cap 6I is formed with an outwardly projecting, externallythreaded, hollow nipple 'S5 whichhas a central aperture G'I'in the endwall' thereof. The nipple is adapted to be threaded 'into anr opening inan engine manifold so as to connect lthe housing to the latter. Acalibrated, bellows-type diaphragm 69% is disposed within thev enlargedalignment with the aperture 61 of the nipple 65.

A rheostat 10, which includes an electrically conductive metallic rod 1Iis secured to the opposite end of the diaphragm 69, and is insulatedtherefrom by suitable insulation 13. The remote end of the shaft 1| isembraced by a winding of wire,

15 so as to form the rheostat 19, which is disposed centrally within thehousing 55. Other forms of rheostats may be employed, the specific oneshown being for the purpose of illustration.

An end cap 11 is threadably connected to the small end of the housing 55and is provided with an outwardly projecting central boss 19, having anaperture 8| therethrough. A pin or stud 83 has its inner end iixedlyconnected to the adjacent end of the rheostat 10. Suitable insulatingmaterial 85 insulates the end of the pin 83 from the rheostat. A coilspring 81 surrounds the inner end of the pin 83 and has its inner endabutting the end of the rheostat 19, and its outer end abutting the endwall of the cap 11. The outer end of the pin 83 projects outwardlythrough the central aperture SI of the end cap boss 19 and is threadedat 89. A hollow, elongated, nutlike member 9| is threadably connected tothe outer end of the pin 83, and the inner end of the member 9| isformed with an enlarged recess 93. The outer end of the end cap boss 19is disposed within the recess 93 and formed with an outturned fiange 95,

which slidably engages the wall of the recess 93. Thus the member 9| canslide longitudinally with respect to the end cap 19, and can be adjustedwith respect thereto by threading it inwardly or outwardly on the pin83.

A pair of longitudinally spaced stationary contacts 99 and I9| aredisposed within the housing 55 so as to engage the rheostat 19. Thestationary contact 99 is connected to one terminal of the electric motor45 Vby means of a wire |03 and battery |05. The contact |0I is connectedto the opposite terminal of the motor 45 through ya wire |01. The wire|91 is provided with a switch |89 which closes only when theengine-ignition is turned on, and is open when the same is olf. A secondswitch III is provided in line |91 which closes when the engine isstarted and a predetermined engine oil pressure obtained. In this waythe motor 45 will not be operated unless the ignition is on, and theengine is actually started, and oil pressure obtained.

The distributor 1 comprises a housing ||3 having a central aperture II5extending longitudinally therethrough and a distributor plate IIGconnected to one end face thereof. The plate I6 Ais provided with aninlet port II1 which communicates with the housing central aperture II5, and with the conduit 9 through a fitting |I9. A distributor element|2| is disposed within the housing aperture I I5, and rotatablysupported in the housing by bearing |23 and snap ring |25. One end ofthe distributor element I2I is provided with a universal coupling '|29for connection with suitable drive means, such as the engine cam shaftfor properly timing the distribution oi the fuel to the cylinder. Thedistributor element |2| is provided at the opposite end from thecoupling |29 with a central longitudinally extending recess I3I whichcommunicates with the inlet port I |1, so as to be filled with the fuelfrom the pump 5. The wall of the distributor element I2| is providedwith an opening |33 which communicates with the recess' 3|. A pluralityof circumferentially, equally spaced passagewaysA are provided inhousing I3 which communicates singly with the distributor opening |33,during rotation of the distributorA element |2I. The housing passageways|35 communicate with outlet ports |31 in the distributor plate IIBsecured to the end face of the housing II3. The outlet ports |31communicate with the conduits I3 through suitable fittings so that uponrotation of the distributor element |2| by, for example, the cam shaftof the engine, the fuel will be discharged through the outlet ports |31to the nozzles II, in timed relation to the engine so as to properlyinject the fuel into the cylinders at the proper time. A groove |40 isprovided in the housing, around the aperture II5, for trapping anyleakage of fuel and a conduit |4| communicates with the grove |49 and isconnected to the intake air manifold. In this way this small amount offuel is sucked into the manifold by vacuum so as to obviate fuel losses.The wall of the rotary distributor |2| is relatively thin so that itwill expand under internal pressure against the wall of the borepreventing leakage. Also, the wall can contract to prevent sticking.

In operation of the system above described the distributor element I2!is driven in timed relation from the engine cam shaft, for example, andthe motor 45 is operated at the proper operating speed by the unit 53.When the engine is at idling speed, the manifold pressure is at itslowest point and the manifold vacuum at its highest point so that thediaphragm bellows 69 of the unit 53 is collapsed and the rheostat 10will move to the right, as viewed in Fig. 1, due to the spring 81. Whenthe rheostat 10 moves to the right the winding 15 will increase theresistance between the stationary contacts 99 and I9I and cause thespeed of the motor 45 to be reduced to its minimum, so that the fueldelivery from the pump 5 to the distributor 1 is at a minimum. Theamount of movement to the right of the rheostat 19y can be adjustablycontrolled by means of the nutlike element 9|. By threading the nutelement 9| inwardly or outwardly on the pin 83, the movement to theright of the rheostat 10 can be controlled. As the nutlike member 9|moves With the pin, it will abut the outer face of the end cap 11 inaccordance with the its threaded position on the pin 83, so that theminimum speed of motor 45, for idling speed of the engine can beproperly adjusted.

When the engine is running at wide open throttle, the manifold pressureis at a maximum and the manifold vacuum at a minimum so that thediaphragm bellows 69 is expanded its full amount, thus moving therheostat 10 to the left as viewed in Fig. 1, 'and reducing theresistance between the stationary contacts 99 and I 9 I. This causes themotor 45 to rotate at its maximum speed so that the maximum fueldelivery from the pump 5 to the distributor 1 is obtained. The amount ofmovement of the rheostat 19, to the left, can be controlled bythreadably adjusting the vend cap 11 on the housing 55 so as to vary thevalue of the spring 81. In this way the maximum speed of the motor 45,for high speeds of the engine can be adjustably controlled to insure theproper fuel delivery for wide open throttle of the engine. The bellows69, of course, will expand or collapse in varying degrees between engineidling speed and wide open throttle, so as to automatically synchronizethe speed of the motor 45 and therefore the fuel delivery from the pumpto the distributor, in accordance with the` manifold pressure.

The operation of the motor 45 at the proper speed causes rotation of theintermeshing pump elements 35 and 31, and withdraws gasoline from thetank 3 through the inlet port I9 into the passageway |1. The fluidpasses toward both ends of the passageway into the inlet chambers aroundthe opposite ends of the pump elements 35 and 31. The iiuid is pumpedinto the outlet chamber surrounding the reduced portions 39 and 4| andout through the outlet port 43 under pressure into the distributor inletport ||1, through the conduit 9. Since the pressure adjacent the endmembers 3l and 33 is under atmospheric pressure there will be no leakageof fuel through these parts. Furthermore, when the pump is not operatingthe fluid will merely drain back under no pressure to passageway l1 andback through the tank.

As the distributor element |2| rotates, the fluid under pressure issupplied through the distributor opening |33 and the passageways |35 tothe outlet ports |31, and therefore to each of the cylinders associatedwith the nozzles in succession.

In certain instances it may be desirable to have the device sensitive tothe engine speed as well as the manifold pressures. This may beaccomplishd by loading the spring 81 through the action of a governorsuitably connected to a speed responsive element on the engine or byraising or lowering the distributor plunger l2| through the action ofthe governor. In this case the opening |33 would be tapered on thelongitudinal axis rather than round.

Formal changes may be made in the specific embodiment of the inventiondescribed without departing from the spirit and substance of theinvention, the scope of which is commensurate with the appended claims.

I claim:

1. In a fuel injection system for a manifoldtype engine, an injectionnozzle, a fuel distributor connected to said nozzle, a fuel pumpconnected to said distributor, variable speed drive means independent ofthe speed of the engine for driving said pump, and means responsive tomanifold pressure for varying the driving speed of said drive means.

2. In a fuel injection system for a manifoldtype engine, an injectionnozzle, a fuel distributor connected to said nozzle, a fuel pumpconnected to said distributor, variable speed drive means independent ofthe speed of the engine for driving said pump, and means responsive tomanifold pressure for varying the driving speed of said drive so as toincrease the pump output at high manifold pressure and decrease the pumpoutput at low manifold pressure.

3. In a fuel injection system for a manifoldtype engine, a multiplicityof injection nozzles, a conduit connected to each nozzle, a fueldistributor having outlet ports communicating with the conduits, saiddistributor having an inlet port, means communicating said inlet portwith said outlet ports in succession, a fuel pump separate from saiddistributor, a conduit connecting the pump outlet with said distributoroutlet, an electric motor independent of the speed of said enginedriving said pump, and means responsive to manifold pressures forvarying the speed of said electric motor independently of engine speedwhereby to increase the speed of said motor at high manifold pressuresand decrease the speed of said motor at low manifold pressures.

4. In a fuel injection system for a manifoldtype engine, an injectionnozzle, a fuel distributor connected to said nozzle, a fuel pumpconnected to said distributor, an electric motor independent of thespeed of said engine driving said pump, variable impedance means forvarying the speed of said electric motor, and diaphragm meansoperatively connected to said variable impedance means and responsive tomanifold pressures for varying said impedance means and therefore thespeed of said electric motor independent of the speed of said engine.

5. In a fuel injection system for a manifoldtype engine, an injectionnozzle, a fuel distributor connected to said nozzle, a fuel pumpconnected to said distributor, an electric motor driving said fuel pump,a bellows-type diaphragm responsive to engine manifold pressures,variable impedance means operatively connected to said diaphragm, andcurrent conducting means connecting said electric motor and saidimpedance means.

6. In a fuel injection system for a manifoldtype engine, a multiplicityof injection nozzles, a conduit connected to each nozzle, a fueldistributor having outlet ports communicating with the conduits, saiddistributor having an inlet port, means communicating said inlet portwith said outlet ports in succession, a fuel pump separate from saiddistributor, a conduit connecting the pump outlet with a distributorinlet, an electric motor independent of the speed of said en- -ginedriving said fuel pump, a housing, a bellowstype diaphragm having oneend thereof connected to said housing, said housing end beingconnectible to said engine manifold whereby said bellows diaphragm isresponsive to manifold pressures, variable resistance means operativelyconnected to the opposite end of said bellows so as to be movabletherewith, stationary contact means engaging said variable resistancemeans, and current conductor means connecting said stationary contactmeans to said electric motor, whereby the operation of said diaphragm inresponse to said manifold pressures will increase the output of saidfuel pump at high manifold pressures and decrease the output of said'pump at low manifold pressures.

7. In a fuel injection system for a manifoldtype engine, an injectionnozzle, a fuel pump connected to said nozzle, variable speed drive meansindependent of the speed of said engine for drivin-g said pump, andmeans responsive to manifold pressure for varying the driving speed ofsaid drive means.

BEN G. PARSONS.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 1,376,841 Iirrill May 3, 19211,597,787 Hausser et al. Aug. 31, 1926 1,745,130 Turner Jan. 28, 19302,126,709 Alden Aug. 16, 1938 2,236,553 Voit et al Apr. 1, 19412,414,617 Summers Jan. 21, 1947 2,439,498 Wallace Apr. 13, 1948 FOREIGNPATENTS Number Country Date 865,115 France Feb. 10, 1941 551,308 GreatBritain Feb. 17, 1943

